Improvement in bark-mills



' W. H. BARBER.

BAM-MILL.

Patented' May 1, 18777.

' mmm Y UNITED STATES PATENT OFFICE;

WILLIAM H. BARBER, 0F ALLENTOWN, PENNSYLVANIA.

IMPROVEMENT IN BARK-MILLS.

Specification forming part of Letters Patent No. 190,182, dated May 1,1877; application filed January 29, 1877. i

improved mill for grinding bark, bone, ce

ment, &c., which shall be so constructed that there will be nobolt-holes or spaces for 'the collection of damp bark to clog the mill;that will be stronger than the ordinary mills; that will require lesslaborto make; that will require less labor and less skill to replaceworn or broken parts; and that shall have fewer parts than the ordinarymill; and will be less liable to get out of order.

The invention consists in providing the grinding or toothed segmentswith dovetail tenons, tting into corresponding slots of the casing andwheel, as will be hereinafter more fully set forth.

A is the, driving-shaft, which revolves upon an adjustable pivot in asocket formed in the discharge-bowl B. Around the upper edge of thedischarge-bowl B are formed lugs or a iiange, C, upon which fit the lugsor ange D, formed around the lower edge of the upper part or case E ofthe mill, so that the said parts B E may be secured to each other bybolts F, passing through the said lugs or flanges G D.

The edges of the bowl B and case E should be rabbeted or halved to eachother, so as to form a close joint even when the said parts are notdrawn close together.

The upper end of the case E is supported by the arms G, theinner ends ofwhich are connected with a collar, H, through which the shaft A passes.

To the shaft A, just -below the collar H, is

keyed the wheel or movable part I ofthe mill, which is made conical inits general form. To the upper part of the wheel I are attached radialcutters J, to break or cut the bark into pieces as it is thrown into themill.

Upon the surfaces of the wheel I and case E are formed graduatedflanges, cutters, or teeth K, to still further break up the bark as itpasses down to the toothed grinding-segments.

Upon thel inner side of the. lower edge of the wheel I are formed lugsor a flange, L, to receive the bolts M, which also pass through the lugsor iiange N, formed upon the inner l side ofthe upper edge of the ring0, to fasten the said ring O against the lower edge of the said wheel I.

rlhe inner surface of the lower edge of the case E and the outer surfaceof the upper part of the ring O have rabbets with inclined or dovetailedshoulders formed in them, which rabbets, in connection with the edges ofthe discharge-bowl B and ring O, form dovetailed grooves Yto receive andclamp the toothed grinding-segments P. This construction enables thesegments P to be made without any bolt-holes through them, and withtheir ends fitted against each other, so that there will be no cavitiesand interstices into which wet bark may stick and form a nucleus of acol lection `that will finally clog themill. This construction alsoenables the grinding-segments to be readily taken out when worn orbroken and replaced with others.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- The combination, in a bark-mill, of detachablegrinding-segments P, having dovetail tenons, with an external casing anda revolving wheel, having doveta'il grooves or seats to receive saidsegments, substantially as and for the purpose set forth.

' WILLIAM H. BARBER.

Witnesses: Y

UnAs. F. BALLIET, GYEUs ZIMMEEMAN.

